Fluid dampened hopper door actuating assembly

ABSTRACT

A railway hopper car having a plurality of hoppers at each side of its center sill, a pair of oppositely opening, longitudinally hinged doors for closing four pairs of doors in unison and a door-actuating motor hydraulically cushioning the opening against the load of the doors and lading in the hoppers.

United States Patent Walter L. Floehr lnventor Toledo, Ohio Appl. No. 682,891

Filed Nov. 14, 1967 Patented Jan. 19, 1971 Assignee Midland-Ross Corporation Cleveland, Ohio a corporation of Ohio FLUID DAMPENED HOPPER DOOR ACTUATING ASSEMBLY 13 Claims, 11 Drawing Figs.

Int. Cl. 861d 7/18, B616 7/28: Fl6f9/O0 Field of Search 74/29, 32,

33, 422; 105/250, 251. 253, 290, 296, 299, 304, 305,240, 311; HES/88.506, 96.6, 96; 267/67, 113, 136

wwmeom [56] References Cited UNITED STATES PATENTS 973,753 10/1910 Campbell 105/25 1X 1,209,809 12/1916 Campbell 105/251 1,835,680 12/1931 Varcin 74/32 2,936,860 5/1960 Peras l88/96X 3,227,100 l/1966 Smith et a1 l05/304X Primary Examiner-Arthur L. La Point Assistant Examiner-Howard Beltran Attorney-Wilmer Mechlin ABSTRACT: A railway hopper car having a plurality of hoppets at each side of its center sill, a pair of oppositely opening, longitudinally hinged doors for closing four pairs of doors in unison and a door-actuating motor hydraulically cushioning the opening against the load of the doors and lading in the hoppers.

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his Attorney FLUID DAMPENED HOPPER DOOR ACTUATING ASSEMBLY BACKGROUND OF THE INVENTION The quick turnarounds required of unit'trains made up of hopper cars for transporting coal and like lading, has led to the development of various door assemblies for such cars for reducing thetime required to unload them. The problem is to open a maximum area in the bottomof the car in a minimum of time without danger to an operator or damage to the asphases of the problem of rapid unloading of hoppers normally closed by hinged doors that the present invention is particularly concerned.

SUMMARY OF THE INVENTION The primary object of the present invention is to provide an improved mechanism for operating a plurality or multiplicity of hinged hopper doors in unison which in an opening operation hydraulically cushions the load imposed upon it.

Another object of the invention is to provide a hopper door assembly which not only includes a self-cushioning operating mechanism for operating a plurality ormultiplicity of hinged doors in unison butalso has its doors so constructed and arranged as unrestrictedly to open the bottoms of the hoppers when the doors are open.

Closing each hopper by a pair of oppositely opening, longitudinally hinged doors, the improved assembly has the doors of each pair hinged to the center and side sill of the car laterally beyond their hopper and, for operating in unison the doors of laterally aligned pairs of longitudinally spaced hoppers at opposite sides of the center sill, mounts in the space extending across the car between the pairs an operating mechanism having at each side of the center sill a vertically movable plunger rack-and-pinion connected both to an v operating shaft extending across the car and to toggles connected to the doorsof the pairs at its sideJlhe mechanism is adapted to swing the doors operated thereby between closed and open positions, in the latter of which the doors are substantially vertical and laterally clear of the discharge openings, and. in an opening operation each plunger advances against a column of liquid for hydraulically cushioning the load imposed on the mechanism.

Other objects and features of the invention will appear hereinafter in the detailed description, be particularly pointed out in the appended claims and be illustrated in the accompanying drawings, in which:

FIGUREDESCRIPTION FIG. 1 is a somewhat schematic side elevational view of a railway hopper car incorporating preferred embodiments of the improved door assembly of the present invention;

FIG. 2 is a fragmentary vertical sectional view on an enlarged scale taken along lines 2-2 of FIG. I and showing a pair of doors and the associated part of the operating mechanism in closed position;

FIG. 3 is a fragmentary vertical'sectional view taken along lines 3-3 of FIG. 1 and showing a part of the structure of FIG. 2, butwiththe doors in open position;

FIG. 4 is a fragmentary sectional view on a further enlarged scale, taken along lines 4-4 of FIG. 2;

FIG. 5 is a fragmentary sectional view on the scale of FIG. 4, taken along the lines 5-5 of FIG. 2;

FIG. 6 isa vertical sectional view takenalong lines 6-6 of FIG.-4;

FIG. 5;

FIG. 7 is a vertical sectional view taken along lines 7-7 of FIG. 8 is a fragmentary sectional view taken along lines 8-8 of FIG. 6; 1

FIG. 9 is a fragmentary sectional view taken along lines 9-9 of FIG. 10;

FIG. I0 is a vertical sectional view taken along lines 10-10 of FIG. 9; and

FIG. 11 is a fragmentary sectional view taken along lines 1 1-11 of FIG. 2.

DETAILED DESCRIPTION Referring now in detail to the drawings in which like reference characters designate like parts, the improved hopper door assembly of the present invention, designated as 1, has been applied for purposes of illustration to a hopper car 2 having eight hoppers 3 divided or separated longitudinally into two sets of foureach. Each quadruple hopper set has its hoppers divided into pairs both laterally and longitudinally, the former by the car's center sill 4 and the latter by a downwardly opening cross well or cavity 5 extending up wardly above the center sill and laterally or transversely across the car. Within each set, the pair of hoppers at each side of the center sill are longitudinally aligned and spaced by the well 5 and each hopper of that pair is laterally or transversely aligned and paired with one of the pair at the sills opposite side. In the illustrated application, one of the improved assemblies I is applied to each set for opening and closing its hoppers in unison. As the assemblies for the two sets are duplicates, only one will be described and only so much of that one has'been illustrated as is needed for an understanding of the invention.

Each hopper 3 of one of the quadruple hopper sets is normally closed by a pair of oppositely opening inner and outer, so-called drop bottom" doors 6 and 7, respectively, which are hinged longitudinally or lengthwise of the car 2 and close, with their distal ends meeting, against opposite, downwardly convergent sides of a laterally V-shaped frame 8 bounding longitudinally or at opposite ends of the hoppers downwardly opening discharge opening 9. Rectangular in horizontal cross section the discharge opening 9 and the frame 8 extend laterally from the adjoining side or web 10 of the center sill 4 to a vertical flange 11 of a side sill 12 extending along the adjoining side of the car above the level of the center sill. The inner and outer doors 6 and 7 are hinged to and depend from an inturned bottom flange 13 of the center sill and an outturnedbottom flange 14 of the side sill, respectively, each beyond the adjoining lateral boundary of the discharge opening 9. So ,mounted, the doors 6 and 7 in opening swing downwardly away from each other to vertical positions, each below the respective bottom flange 13 or 14 and substantially clear of a vertical projection of the discharge opening. To enable the doors to assume. such open positions without contacting the ground at either side of the underlying rail 15, the lower mounted inner door 6 necessarily is the shorter. The corresponding doors 5 and 6 of the two pairs closing the discharge openings 9 of the pair of longitudinally spaced hoppers 3 at each side of the center sill 4, are connected across the well 5 by a pair of laterally spaced connecting beams 16, each ofZ- or other suitable shape and fixed to and extending across the outside of its pair of corresponding doors adjacent their distal ends.

For operating the several pairs of doors of the hoppers in unison, the improved assembly I has mounted in the well 5 an operating mechanism 17 including at each side of the center sill 4 a vertically movable or reciprocable plunger or piston 18 positioned laterally between the center sill and the side sill 12 at its side, roughly in longitudinal alignment with the joints 19 between the distal ends of the doors 6 and 7 of the adjoining pairs in their closed positions. Each plunger 18 preferably is slidably mounted and enclosed or contained in a housing 20 which itself conveniently is mounted on an outrigger 21 fixed to an outstanding from its side of the center sill 4. The plungers 18 are drivable connected for vertical reciprocation to a common operating shaft 22 rotatable about a horizontal axis and extending horizontally of the car 2 in and preferably through the well 5, with its ppposite ends suitably journaled on and projecting outwardly or outboardly beyond the vertical flanges ll of the side sills 12. For the preferred driving connection, the operating shaft 22 is offset laterally, radially or longitudinally from the plungers l8 and drivably connected to each thereof by one or a pair of axially spaced pinions fixed or keyed against relative rotation to the shaft and intermeshing with or engaging a longitudinally facing upper rack 26 on and extending longitudinally or vertically along the contiguous or adjoining side of the plunger. For supporting the operating shaft 22 intermediate its ends and protecting the pinions 23, each pinion preferably is contained or enclosed in an upper gear casing 25 on or rigid with and forming part of the related or associated housing 20 and the shaft extends through and is journaled in each casing at opposite sides of the pinion therein.

Each plunger 18 preferably is a triple rack bar, carrying, mounting or having formed on it in addition to the upper rack 24, a pair of diametrically opposed, laterally facing lower racks 26, suitably extending downwardly to the plungers lower end 27 and upwardly to vertically overlap and circumferentially bracket the relatively normally or angularly facing upper rack. it is through these lower racks 26 that the vertical rectilinear motion imparted to each plunger 18 by the operating shaft 22 is translated into opening and closing movements of the doors 6 and 7 of the pairs at its side of the center sill 4. The translation is effected by drivably connecting each lower rack 26 to one end of a pair of toggles 28 and 29, which are connected at their opposite ends to the adjoining pair of inner door 6 and outer doors 7, respectively, conveniently through the beams 16 by which the doors of each pair are rigidly connected. Differing in length, as befits the difference in length of the inner and outer doors 6 and 7, but otherwise identical, each of the toggles 28 and 29 has as its inner portion a crank arm 30 fixed at its inner end to a crankshaft 31 extending horizontally, longitudinally of the car 2, below and normal to the operating shaft 22. As its outer portion, each toggle 28 and 29 has a link 32 connected at one end for relative vertical pivoting to the outer end of its crank arm 30 and at the other end, preferably universally, as by a crosspin connector 33, to the related connecting beam 16 between the door 6 or 7 of the pair connected thereby. The crankshafts 31 are rotatably mounted at opposite sides of the plunger 18 in a lower gear casing 34 rigid with and forming part of the housing 20 and conveniently formed as an integral part of the outrigger 21. Straddling or embracing and each faced by one of the lower racks 26, the crankshafts 31 are drivable connected to the facing racks by suitably sector pinions or pinion gears 35 con tained within the casing 34 and each fixed or keyed against relative rotation to one of the shafts and intermeshing with or engaging the facing, confronting or adjoining rack.

Extending vertically through the vertically spaced upper and lower gear casing 25 and 34, each plunger 18 between and beyond those casings, slides in tubular intermediate and end portions 36 and 37, respectively, of the housing 20 which, for the preferred cylindrical plunger, are appropriately cylindrical with the end portions closed at their outer ends. Each end portion 37 contains an end chamber 38 in which rides or slides and is contained or housed one of the upper and lower ends 39 and 27, respectively, of the plunger 18. With this arrangement and suitably gasketed or sealed against fluid leakage, the housing 20, even if only containing air under atmospheric or higher pressure, will resist movement of the plunger 18 in either In direction by the columns of air presented to its ends 25 and 37.

if, instead of air, each housing 20, as preferred, is tilled with oil or other suitable liquid, as through a normally plugged full port 40 in its top, the plunger 18 therein not only is resisted in movement but cannot move in any direction without displacing oil from the chamber 38 at its then leading end and, by requiring the oil so displaced to pass through a suitably restricted orifice or passage, the oil can be made to resist and cushion large forces suddenly applied to the plunger and yet have little effect upon its movement under low forces, gradually applied. This is the result desired in the improved assembly, with the sudden, large forces primarily those imposed by the lading on the doors 6 and 7 of the several hoppers 3 of the assembly in an opening operation and the small, gradually applied forces those required to close the doors against the force of gravity after the unloading has been completed. The exchange of oil between the end chambers 38 preferably is performed within the housing 20, with the choking or throttling produced by a restricted passage between the ends 25 and 37 of the plunger 18, which conveniently may be either through or around the plunger, with the restriction in the latter case the annular space orifice 41 in one or each of the chambers between its sidewall 42 and the end portion of the plunger therein contained.

In the illustrated embodiment, each plunger 18 is in its down position when the doors 6 and 7 connected thereto are closed and at that time, the toggles 28 and 29 connected to the doors are collapsed or retracted with their links 32 folded into and stopped against their crank arms 30. Each toggle as a whole and its elements are then preferably disposed in a line extending through the axes of its crankshaft 31 and its pivotal connection to the related connecting beam 16 and substantially normal to the common plane of the outsides of the doors connected by the beam, thus imposing on the housing 20 and substantially relieving the trains of gears therein of the load of the doors and any lading in their hoppers.

The operating mechanism 17 can be locked in closed position or condition in any suitable manner, as by locking the operating shaft 22 against rotation. If in the initial assembly any adjustment is needed in any toggle 28 or 29 in the radial spacing in closed position between its crank axis and that of the pivot of its connector 33 to the related connecting beam 16 to correct the fit of the doors against their sides of the frame 8, this is readily accomplishable, as by adjustably or shiftably mounting on the connecting beam the bracket or clevis 43 through which the connector 33 is connected thereto.

in an opening operation each plunger 18 is moved or advanced to its up position by turning of the operating shaft 22 in the proper direction, causing the related crank arms 30 to swing in opposite directions apart from each other and corresponding extension or unfolding of the toggles 27 and 28, this continuing pg, until the doors have reached their substantially vertical open positions, It is in this operation that the oil filling each housing 20 and opposing, with the column in the upper of the chambers 38 therein, upward movement of the plunger, comes into play in cushioning the force applied to the plungers by the lading in the several hoppers 3 as soon as the toggles 28 and 29 are disturbed and begin to break from their in-line closed positions.

Slowing the upward movement of each plunger and, correspondingly, the downward swing of the doors by the restriction imposed by the annular orifice 41 in each housing 20 on the flow of the necessarily displaced oil from the upper to the lower end chamber 38 the operating mechanism by the hydraulic cushioning obtained in the housings, is effectively protected from the severe shocks to which it otherwise would be subjected by the collective force of the lading in the several hoppers 3 whose doors 6 and 7 it operates. Conversely, in a closing operation, each plunger 18 will be moved downwardly by the operating shaft 22 to retract the toggles 28 and 29 and close the doors and the plungers lower end 27 will act against the column of oil in the lower of the end chamber 28 and displace oil to the upper chamber through the restricted orifice 41. However, in this case there is only the weight of the doors to contend with and the force will be gradually applied and relatively low. Consequently, the displaced oil will flow between the chambers practically unimpeded by the restricted orifice.

in both opening and closing operations, the operating mechanism 17 will be operated by turning the operating shaft 22 in the appropriate direction, The shaft can be so turned manually byapplying a suitable turning tool to either of its ends 44 or by power by drivably connecting it at an end or elsewhere to an air or other suitable drive motor (not shown), and an installation for power operation usually will provide for alternate manual operation in the event of power inavailability or failure at a particular destination. Whether the operation is manual or power, an opening force need be applied to the operating shaft only to the point at which the downward force of gravity on the doors and any lading in the hoppers begins to act on the plungers 18, after which that downward force will sufiice to complete the opening. it is then that the hydraulic cushioning is of most benefit, its retarding or slowing of the opening preventing wrenching'of the turning tool from the operator in amanual operation and drastically reducing the strain on the motor in a power operation so that a clutch in the connection between the operating shaft and the turning tool or the motor usually .will not be needed.

From the above detailed description it will be apparent that there has been provided an improved hopper door assembly which not only enablesthe bottoms of hoppers to be opened to the maximum but also protects itself in opening from damage from the opening force produced by lading, even when a multiplicity of of hoppers are involved. It should be understood that the described and disclosed embodiment is merely exemplary of the invention and that all modifications are intended to be included that do not depart from the spirit of the invention and the scope of the appended claims.

lclaim:

l. A hopper door assembly for a railway hopper car, comprising door means swingable vertically between open and closed positions, housing means fixed to the car, plunger means slidably housed for axial movement in said housing means, means connecting said door and plunger means for axial movement of said plunger means in opposite opening and closing directions respectively on opening and closing of said door means,-and fluid-cushioning means in said housing means including chamber means containing part of and tilled with fluid acting directly on said plunger means for yieldably resisting movement thereof in an opening direction.

2. A hopper door assembly according to claim 1, including operating means drivably connected to the plunger means for therethrough opening and closing the door means.

3. A hopper door assembly according to claim 2, wherein the chamber means is filled with oil, and the plunger means acts endwisc on and displaces the oil from the chamber means in moving in an opening direction, and including restricted orifice means connected to the chamber means for controlling displacement of said oil the efrom.

4. A hopper door assem ly according to claim 3, including second chamber means in the housing and filled with oil, and

wherein the first-named and said second chamber means con tain opposite ends of the plunger means throughout the range of axial movement thereof, oil is displaced from one to another of said chamber means on movement of the plunger means in either direction, and the restricted orifice means through which the oil passes is in the housing means between opposite ends of the plunger means.

5. A hopper door assembly according to claim 4, wherein the restricted orifice means is between confronting sides of the plunger and housing means. i

6. A hopper door assembly according to claim 5, wherein the housing is filled with oil.

7. A hopper door assembly according to claim 3, wherein the door means include a pair of longitudinally hinged oppositely opening doors normally closing a downwardly opening discharge opening of a hopper of the car at one side of a movable vertically in said housing, and the connecting means center sill thereof, the housing means include a housing mounted in a well extending laterally of the car at an end of include a pair of vertically disposed toggles mounted in said well and connected to said housing at opposite sides of said plunger and each donnected to one of said doors, and including a rack-and-pmron dl'lVlIlg connection between each toggle and said plunger.

8. A hopper door assembly according to claim 7, wherein the operating means include an operating shaft extending laterally of the car in the well, and a rack-and-pinion drive connecting between said shaft and the plunger.

9. A hopper door assembly according to claim 8, wherein the plunger has a pair of oppositely facing racks at and extending longitudinally along oppositesides thereof, each toggle includes a crank arm having a crankshaft pivoted to the housing, arid each crankshaft has fixed against relative rotation thereto a pinion engaging one of said racks.

. 10. A hopper door assembly according to claim 9, wherein the rack-and-pinion driving connection between the plunger and the operating shaft includes a rack on the plunger straddled by and facing substantially normal to the facings of the first-named racks.

11. A hopper door assembly according to claim 3, wherein the car has laterally aligned pairs of hoppers at opposite sides of a center sill thereof, the door means include a multiplicity of pairs of longitudinally hinged oppositely opening doors each pair'closing a downwardly opening discharge opening of one of the hoppers, the housing means includes a pair of housings mounted at opposite sides of said center sill in a well extending laterally of the car between longitudinally adjoining of said hoppers, the plunger means include a plunger axially slidable vertically in each housing, the operating means include an operating shaft extending laterally of the car in said well and rack-and-pinion connected to each plunger, said doors of each pair are inner and outer doors hinged beyond lateral boundaries of the discharge opening closed thereby to the bottom respectively of said center sill and an adjoining side sill of the car, each door is connected for swinging in unison to a corresponding door of a longitudinally adjoining pair by a connecting beam extending across said well therebetween, and the connecting means include at each side of said center sill a pair of vertically disposed toggles connected at inner ends to the adjoining housing at opposite sides of the plunger therein for pivoting about horizontal axes extending longitudinally of the car and each universally connected at an outer end to one of said beams between the doors connected thereby, anda rack-and-pinion driving connection between each toggle and the plunger in the adjoining housing.

12. A hopper door assembly according to claim 11, wherein the fluid cushioning means include a pair of chambers in each housing at and containing opposite ends of the plunger therein, the housing is filled with oil for preventing movement of the plunger in either direction except by displacement of oil from one of said chambers, and the displaced oil is transferred between said chambers in each housing through a restricted passage in each housing between ends of a plunger therein for cushioning movement of the plunger in an opening direction.

13. A hopper door assembly according to claim 3, wherein the car has a plurality of hoppers each having a downwardly opening discharge opening laterally extending substantially from a center sill of the car to a side sill thereof, the door means include a plurality of pairs of longitudinally hinged oppositely opening inner and outer doors each pair closing one of said discharge openings, and the inner and outer doors of each pair are hinged beyond lateral boundaries of the related opening to bottoms respectively of the center sill and the adjoining side sill. 

1. A hopper door assembly for a railway hopper car, comprising door means swingable vertically between open and closed positions, housing means fixed to the car, plunger means slidably housed for axial movement in said housing means, means connecting said door and plunger means for axial movement of said plunger means in opposite opening and closing directions respectively on opening and closing of said door means, and fluid-cushioning means in said housing means including chamber means containing part of and filled with fluid acting directly on said plunger means for yieldably resisting movement thereof in an opening direction.
 2. A hopper door assembly according to claim 1, including operating means drivably connected to the plunger means for thereThrough opening and closing the door means.
 3. A hopper door assembly according to claim 2, wherein the chamber means is filled with oil, and the plunger means acts endwise on and displaces the oil from the chamber means in moving in an opening direction, and including restricted orifice means connected to the chamber means for controlling displacement of said oil therefrom.
 4. A hopper door assembly according to claim 3, including second chamber means in the housing and filled with oil, and wherein the first-named and said second chamber means contain opposite ends of the plunger means throughout the range of axial movement thereof, oil is displaced from one to another of said chamber means on movement of the plunger means in either direction, and the restricted orifice means through which the oil passes is in the housing means between opposite ends of the plunger means.
 5. A hopper door assembly according to claim 4, wherein the restricted orifice means is between confronting sides of the plunger and housing means.
 6. A hopper door assembly according to claim 5, wherein the housing is filled with oil.
 7. A hopper door assembly according to claim 3, wherein the door means include a pair of longitudinally hinged oppositely opening doors normally closing a downwardly opening discharge opening of a hopper of the car at one side of a center sill thereof, the housing means include a housing mounted in a well extending laterally of the car at an end of said hopper, the plunger means include a plunger axially movable vertically in said housing, and the connecting means include a pair of vertically disposed toggles mounted in said well and connected to said housing at opposite sides of said plunger and each connected to one of said doors, and including a rack-and-pinion driving connection between each toggle and said plunger.
 8. A hopper door assembly according to claim 7, wherein the operating means include an operating shaft extending laterally of the car in the well, and a rack-and-pinion drive connecting between said shaft and the plunger.
 9. A hopper door assembly according to claim 8, wherein the plunger has a pair of oppositely facing racks at and extending longitudinally along opposite sides thereof, each toggle includes a crank arm having a crankshaft pivoted to the housing, and each crankshaft has fixed against relative rotation thereto a pinion engaging one of said racks.
 10. A hopper door assembly according to claim 9, wherein the rack-and-pinion driving connection between the plunger and the operating shaft includes a rack on the plunger straddled by and facing substantially normal to the facings of the first-named racks.
 11. A hopper door assembly according to claim 3, wherein the car has laterally aligned pairs of hoppers at opposite sides of a center sill thereof, the door means include a multiplicity of pairs of longitudinally hinged oppositely opening doors each pair closing a downwardly opening discharge opening of one of the hoppers, the housing means includes a pair of housings mounted at opposite sides of said center sill in a well extending laterally of the car between longitudinally adjoining of said hoppers, the plunger means include a plunger axially slidable vertically in each housing, the operating means include an operating shaft extending laterally of the car in said well and rack-and-pinion connected to each plunger, said doors of each pair are inner and outer doors hinged beyond lateral boundaries of the discharge opening closed thereby to the bottom respectively of said center sill and an adjoining side sill of the car, each door is connected for swinging in unison to a corresponding door of a longitudinally adjoining pair by a connecting beam extending across said well therebetween, and the connecting means include at each side of said center sill a pair of vertically disposed toggles connected at inner ends to the adjoining housing at opposite sides of the plunger therein for pivoting about horizontal axes extending longItudinally of the car and each universally connected at an outer end to one of said beams between the doors connected thereby, and a rack-and-pinion driving connection between each toggle and the plunger in the adjoining housing.
 12. A hopper door assembly according to claim 11, wherein the fluid cushioning means include a pair of chambers in each housing at and containing opposite ends of the plunger therein, the housing is filled with oil for preventing movement of the plunger in either direction except by displacement of oil from one of said chambers, and the displaced oil is transferred between said chambers in each housing through a restricted passage in each housing between ends of a plunger therein for cushioning movement of the plunger in an opening direction.
 13. A hopper door assembly according to claim 3, wherein the car has a plurality of hoppers each having a downwardly opening discharge opening laterally extending substantially from a center sill of the car to a side sill thereof, the door means include a plurality of pairs of longitudinally hinged oppositely opening inner and outer doors each pair closing one of said discharge openings, and the inner and outer doors of each pair are hinged beyond lateral boundaries of the related opening to bottoms respectively of the center sill and the adjoining side sill. 